Seeing the World Through Our Pet’s Eyes

What do dogs and cats see when they look at the world around them? Are cats and dogs colorblind? How well can they see at night? These common questions, and many more, are the tip of the iceberg for many pet parents who want to know more about their canine and feline friend’s eyesight.

Dog Eyesight

The anatomical structure of a dog’s eye is relatively similar to that of a human’s. A canine’s eye is made up of four main parts:

• Cornea
  This clear and rounded outer part of the eye covers and helps protect the iris and pupil. The cornea’s purpose is to assist in focusing light rays on the retina at the back of the eye.
• Iris
  The iris is the colored portion of a dog’s eye. It can help control the light let in by contracting or expanding the pupil.
• Pupil
  Like a person’s eye, a dog’s pupil is the round, black opening in the middle of the iris. The pupil allows light to pass through to the retina.
• Lens
  The lens is a transparent structure within the eye, behind the iris. It can help with focusing incoming light on the retina.

For many dogs, their iris is a brown, gold, or amber hue, but some dogs can also have blue eyes—Huskies being the most well-known. It is also possible for dogs to have heterochromia, a condition where they have two different colored eyes. Heterochromia is relatively common in Australian Shepherds.

The size of a dog’s pupils can also give insight to how they’re feeling. In a situation where your pup feels stressed or fearful, their fight or flight instincts may kick in and cause their pupils to expand. Your dog’s pupils can also expand when they are excited. This often occurs when they are playing and their hunting instinct gives them a boost of adrenaline.

Dog Eyesight at Night

Compared to people, canines have a few vision disadvantages, such as the inability to see finer details, less accurate depth perception, and a more limited view of the color spectrum. However, they do have an advantage when it comes to their ability to see in the dark.

This ability to see better in low-light conditions can be attributed to the unique structure of their eyes. With larger pupils than a person, dogs can allow more light to enter their eyes, thus allowing them to have better vision in darker settings. Their eyes also have far more rods, which are responsible for vision with low light. A part of this enhanced eyesight is that they can also distinguish shapes and motion better at night.

The tapetum lucidum also deserves recognition. This thin, reflective membrane, located in the rear of the eye, helps reflect the light not absorbed by the rods toward the retina instead. This efficient process allows pups to take in more light, thus improving their ability to see at night. This tissue also gives your dog’s eyes the glowing effect when you snap a photo with the flash on or shine a light at them in the dark.

What Colors Can a Dog See?

It has long been believed that dogs can only see in black, white, and maybe some shades of gray, but is that true? How dogs perceive color is mainly attributed to the structure of their eyes. There are two types of cells in the eye’s retina that help discern light and color. Rods can help distinguish various light levels and motions, while cones work to distinguish different colors. For comparison, human eyes have three types of cones that pick up combinations of red, blue, and green, while dogs only have two cones that discern blue and yellow.

With fewer cones, this gives dogs a more limited perception of colors—this is known as dichromatic vision. In humans, dichromacy is a type of color blindness. It is believed that a dog’s vision may be similar to that of a human with red-green color blindness, meaning that it’s difficult for them to distinguish the two colors from one another.

Instead of thinking that dogs can’t see colors, it may be more accurate to say that dogs don’t see “true” color and have a more limited color spectrum. For instance, orange and green may have a yellow tint, purple may be mistaken for blue, and red will likely appear dark brown.

How To Know if Your Dog Is Losing Eyesight

Over time, a dog’s eyesight can decline, either due to old age or various optical-related health issues. No matter the reason, there are a few tell-tale signs for which you can watch.

• Your dog shows hesitancy to move about in the dark.
  As your dog ages, they may experience some retinal degeneration, which may cause them to have poor vision in low-light or dark settings. You can help your best bud by providing night lights throughout your home and bringing a flashlight whenever you take them outside at night.
• They bump into objects such as furniture or walls.
  When a dog’s vision begins to decline, you may notice that they are bumping into your chairs, tables, or couches more. They may also cut corners too much, miss a doorway, and accidentally boop their nose on a door or wall. It can be helpful to your pup not to rearrange furniture or items such as their bed or bowls.
• Their reflexes don’t seem as acute.
  Another indicator that your dog’s vision is changing is that their reflexes aren’t as quick or responsive as they once were. You may especially notice this when you toss your dog a treat or toy, as they may not be able to catch them every time like they used to.
• Your dog may become uncomfortable with everyday activities.
  When vision is affected, it’s not unusual for your dog to become hesitant toward activities that used to be an everyday occurrence. Car rides, for instance, may become a worry since your dog may not be able to see well when jumping in and out of the car.
• Sunlight may become an irritant.
  You might notice your dog having a sudden reaction to sunlight—this may be especially true for dogs with cataracts. As the eyes are exposed to brighter light, the pupils will shrink, and the light will pass through the denser, cloudier portion.

You know your dog best, and if you believe they are acting differently than usual or if they are experiencing any of the aforementioned signs, it’s essential that you contact your veterinarian right away. Not only can your veterinarian assess your dog’s condition, but they can perform a complete diagnostic exam to better understand your dog’s health and discuss any possible treatment and management options.

Cat Eyesight

If you’ve ever gazed into the eyes of a feline, then you’re already aware of the beauty and brilliance they hold. When first born, kittens’ eyes will stay shut for a short while, roughly two weeks. Although you may only catch glances, their irises will be blue. Around the time they turn three or four months old, you may notice their eye color changing, although some may stay blue for the rest of their life. Other possible colors include green, yellow, gold, orange, and copper. Cats can also have two different colored eyes, which is also referred to as odd-eyed or heterochromia. They can also have dichromatic eyes, which is when there are two different colors in one iris.

The main anatomical structure of a cat’s eye is similar to that of a canine’s. There’s the cornea, which is the clear and rounded outer part of the eye. It helps protect the iris and pupil and focuses light on the retina. The iris is the colored part of a cat’s eye and it controls the light that’s let into the eye by expanding or contracting the pupil. Like a dog and human’s eye, the pupil in a cat’s eye is the round, black opening in the middle that allows light to pass through to the retina and the lens is a transparent structure within the eye that’s behind the iris. It can also help with focusing light on the retina.

The most notable attribute of a cat’s eye is the pupil. Vertical and slit-like, their pupils can shrink to a thin line and expand drastically to the point that they appear to take up the entire iris. While this helps improve your cat’s ability to see in the dark, their pupil size can also give insight into how they feel.

For instance, whenever a cat’s pupils become narrow, and it’s accompanied by purring, this could indicate that your cat is happy and content. If purring isn’t present, but your cat’s pupils are much thinner than normal or their eyes are squinting, this could mean they are feeling a bit more angsty. Larger-than-normal pupils could mean that your cat is scared, perhaps by the vacuum, or they could be excited, which may occur if you bring out a favorite toy.

Do Cats Have Good Eyesight in the Dark?

Felines can have impressive seeing abilities in low-light and dark conditions, but their eyesight isn’t equivalent to night vision, as many believe. Compared to people, cats have significantly better sight in the dark, and this can be directly attributed to their higher number of rods. These photoreceptor cells allow felines to distinguish objects and motion better in unideal lighting situations.

Cats also have better vision in dark settings due to the “mirror layer” behind their retina, called the tapetum lucidum. This helps reflect the light absorbed by the eye. If light enters the eye but does not hit a rod, it will reflect off this thin layer and have a second chance to hit a rod. This mirror layer is also why your cat’s eyes appear to glow in the dark.

What Colors Can a Cat See?

Like dogs, there has been a long-standing belief around our feline friends that they can only see in black and white. The truth is quite the contrary. Although cats may not be able to see as many colors on the spectrum as people, their perception of color can be compared to someone who is color blind.

Cats only have two types of cones to input color—one for blue and one for green. They do not have one for red. Having two types of cones is known as dichromacy while having three is identified as trichromacy. Cats have a more diluted view of color with only a couple of receptors, and specific colors may blend together.

How To Tell if a Cat Is Losing Eyesight

Whether from any number of health conditions or old age, it’s possible that your cat’s eyesight could change at some point in their life, with the likeliness increasing as they get older. By taking your cat to regular veterinary check-ups, you have a greater chance of catching any issue early on, which could also help their treatment process.

Aside from receiving an official examination, there are other ways to tell if your cat’s eyesight is declining. These include:

• Your cat has become clumsy.
  Most cats are relatively skilled in delicately walking across narrow surfaces or swerving around items on a shelf. However, when your feline friend’s sight becomes affected, you may notice them doing some things that appear ditsy or uncoordinated. For example, bumping into furniture or the walls or missing a toy thrown their way could indicate that their eyesight has become affected.
• Their jumps aren’t as calculated.
  When your cat’s eyesight declines or changes, their depth perception may also be affected. You might notice your cat missing their jumping target or landing slightly more unbalanced. Pay attention if your cat appears more hesitant when jumping, as this could indicate that things seem more blurred to them.
• They appear to be wary as they walk around.
  This may be particularly true if your best pal has already been bumping into objects more or if they’ve had a slight fall on the stairs. You may notice that they are also walking much slower in general.
• Your cat’s eye has changed appearance.
  Looking at your cat’s eyes and comparing them to one another could also help you discern if something more is going on. For instance, your cat’s pupils should be the same size, but if one appears bigger or smaller than the other, this could indicate that something more is going on below the surface. Likewise, discoloration, redness, or cloudiness can also be warning signs of an underlying health issue. Also, note if your cat is squinting more than usual or keeping one eye closed.
• They are meowing more than usual.
  If your cat becomes disoriented due to not being able to see as well as they used to, this could cause them to experience stress or anxiety. This can be particularly true for cats that lose their sight suddenly. Meowing more can signify that your cat is expressing their distress and trying to communicate with you that they might need help.

Although it may be an adjustment for you and your cat when their sight changes, you can help provide them with a safe and accommodating environment in many ways. For instance, try to keep your floor space cleaned up, as this can eliminate tripping hazards. It’s also helpful not to rearrange furniture or move your cat’s bed, litterbox, or bowls (unless for accessibility reasons) since your cat is familiar with your current home layout.

It may also be helpful to shut doors to areas your cat doesn’t need to be in, such as a closet or bathroom. This can help eliminate the issue of them accidentally getting trapped or lost. If you’re worried about your cat around stairs, you can put up a safety gate or line the top stair and landing with cat-safe lemon oil. Whenever your cat smells the oil, they’ll know to associate it with a step, allowing them to safely move about without giving up their mobility options—this works well for dogs too.

As you and your cat go about your day and move throughout your home, your feline friend may appreciate you speaking aloud, especially when you enter the room with the other. Although your cat might not be able to see you, being able to hear you can reassure them of your presence and whereabouts.

Anytime your cat or dog’s eyesight becomes affected, it becomes an adjustment for them as much as it does for you. Remember to stay patient with them as they get used to their new way of navigating. Try putting yourself in their shoes (or paws) and consider how you can make their home more accessible and safer for them. Even if their vision isn’t as good as it once was, that doesn’t mean your best pal will need to sacrifice any of the fun and healthy lifestyle they already have.

_{An ASPCA Pet Health Insurance plan can help you with eligible costs for covered conditions like surgery expenses for accidents and help provide peace of mind that your pet can receive the care they need. Check out our online resources to learn more about your insurance options and get a free quote today. The information presented in this article is for educational and informational purposes only and does not constitute or substitute for the advice of your veterinarian.}

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